1. Field of the Invention
This invention relates to locks and, more particularly, to a combination lock that is controlled through electrical logic circuits, and the like.
2. DESCRIPTION of the PRIOR ART
Pushbutton combination locks have failed to achieve a wide degree of public acceptance because of a number of disadvantages. Among these disadvantages, it appears that inadequate lock security may provide the main reason for this failure. In this respect, some pushbutton locks partially reveal the combination because of the indication of wear that shows after some use of only a few of the buttons in the array that the lock presents. The "feel" that a number of these locks give to the touch of someone engaged in tampering with the combination also is a clear disadvantage, as well as the very limited number of combination possibilities that are available to locks of this nature.
Further in this respect, pushbutton combination locks heretofore have been expensive to manufacture and unreliable in operation because of the large number of small, complicated and failureprone parts that these locks require. In addition to these foregoing problems, pushbutton locks often involve complicated procedures for changing the combination, in some cases requiring an inventory of parts which must be substituted in an existing lock through painstaking assembly and disassembly. Clearly, there is a need for a relatively secure combination lock that satisfies these needs.